Merge pull request #1475 from atalw/2022-04-paymentforwarded-event

Expose `next_channel_id` in `PaymentForwarded` event

diff --cc fuzz/src/chanmon_consistency.rs
Simple merge

diff --cc lightning/src/chain/chainmonitor.rs
Simple merge

diff --cc lightning/src/chain/mod.rs
Simple merge

diff --cc lightning/src/ln/channelmanager.rs
Simple merge

diff --cc lightning/src/ln/functional_test_utils.rs
Simple merge

diff --cc lightning/src/ln/functional_tests.rs
Simple merge

diff --cc lightning/src/ln/reorg_tests.rs
Simple merge

diff --cc lightning/src/ln/shutdown_tests.rs
Simple merge

diff --cc lightning/src/util/events.rs
Simple merge

diff --cc lightning/src/util/test_utils.rs
Simple merge